1. Field of the Disclosure
This disclosure relates generally to devices for use in high temperature environments, including, but not limited to, refrigerant evaporation devices for conducting heat away from or to payloads.
2. Brief Description of the Related Art
Wellbores for the production of hydrocarbons (oil and gas) are drilled using drilling and evaluation devices and tools. Wireline tools are used to log such wells after drilling. Current drilling and logging tools include a variety of sophisticated sensors, electronic circuits and hydraulic components to perform complex drilling operations and to obtain a variety of measurements downhole to determine various parameters of the formation and to evaluate and monitor drilling and wireline operations. Severe downhole environmental conditions exist in deep wells, such as temperatures up to 300° C. and pressure above 10,000 psi. Some wells are drilled up to 10,000 meters. Such downhole conditions make high demands on the materials and electronics used for drilling, making measurement-while-drilling (MWD) and wireline tool measurements. Thermoelectric coolers, based on the Peltier effect, and other types of devices, such as flasks have been used to maintain the temperatures of certain components about 50° C. below the ambient temperature of 200° C. However, fluid evaporation has generally not not been provided with external cooling during downhole operations.
The disclosure provides apparatus and methods for cooling components of downhole tools utilizing evaporation of a refrigerant downhole.